MDEV-6450 - MariaDB crash on Power8 when built with advance tool chain

Part of this work is based on Stewart Smitch's memory barrier and lower priori
patches for power8.

- Added memory syncronization for innodb & xtradb for power8.
- Added HAVE_WINDOWS_MM_FENCE to CMakeList.txt
- Added os_isync to fix a syncronization problem on power
- Added log_get_lsn_nowait which is now used srv_error_monitor_thread to ensur
  if log mutex is locked.

All changes done both for InnoDB and Xtradb

1 files changed, 44 insertions, 0 deletions

diff --git a/include/my_cpu.h b/include/my_cpu.h
new file mode 100644
index 00000000000..026b92c1b74
--- /dev/null
+++ b/include/my_cpu.h
@@ -0,0 +1,44 @@
+/* Copyright (c) 2013, MariaDB foundation Ab and SkySQL
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; version 2 of the License.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02111-1307  USA
+*/
+
+/* instructions for specific cpu's */
+
+/*
+  Macros for adjusting thread priority (hardware multi-threading)
+  The defines are the same ones used by the linux kernel
+*/
+
+#if defined(__powerpc__)
+/* Very low priority */
+#define HMT_very_low() asm volatile("or 31,31,31")
+/* Low priority */
+#define HMT_low() asm volatile("or 1,1,1")
+/* Medium low priority */
+#define HMT_medium_low() asm volatile("or 6,6,6")
+/* Medium priority */
+#define HMT_medium() asm volatile("or 2,2,2")
+/* Medium high priority */
+#define HMT_medium_high() asm volatile("or 5,5,5")
+/* High priority */
+#define HMT_high() asm volatile("or 3,3,3")
+#else
+#define HMT_very_low()
+#define HMT_low()
+#define HMT_medium_low()
+#define HMT_medium()
+#define HMT_medium_high()
+#define HMT_high()
+#endif